Double venturi pressure regulator

ABSTRACT

A fluid pressure regulator casing has a piston valve in a cylinder coactive with an adjustable spring-pressed diaphragm to control flow of fluid from an inlet passage through an outlet duct across which extends a venturi tube for subjecting both said diaphragm and said piston valve to the pressure produced by fluid flow through said outlet duct past the venturi tube, so that the regulator may be small and may have greater capacity or outlet flow and less pressure drop in relation to prior regulators. A locking ring coaxially rotatable on a resilient flange on the casing coacts with said flange to lock and release an adjusting knob for the regulation of the spring pressure on the diaphragm with a minimum of possibility of unintentional rotation of the knob from its adjusted position.

United States Patent- Semon 15] 3,643,683 [4 1 Feb. 22, 1972 [54] DOUBLEVENTURI PRESSURE REGULATOR [72] Inventor: Albert L. Semon, ll Eliot PL,Short Hills,

[221 Filed: Sept. 23, 1970 [21] Appl. No.: 74,746

3,392,749 7/1968 Gneiding et al ....l37/505.26 X

Primary Examiner-Henry T. Klinksiek Attorney-Harry B. Rook [57] ABSTRACTA fluid pressure regulator casing has a piston valve in a cylindercoactive with an adjustable spring-pressed diaphragm to control flow offluid from an inlet passage through an outlet duct across which extendsa venturi tube for subjecting both said diaphragm and said piston valveto the pressure produced by fluid flow through said outlet duct past theventuri tube, so that the regulator may be small and may have greatercapacity or outlet flow and less pressure drop in relation to priorregulators. A locking ring coaxially rotatable on a resilient flange onthe casing coacts with said flange to lock and release an adjusting knobfor the regulation ofv the spring pressure on the diaphragm with aminimum of possibility of unintentional rotation of the knob from itsadjusted position.

5 Claims, 4 Drawing Figures DOUBLE VENTURI PRESSURE REGULATOR BACKGROUNDOF THE INVENTION 1. Field of the Invention This invention relates tofluid pressure regulators of the type including a valve casing that hasan inlet and an outlet between which is a valveport and a valve seatwith which cooperates a piston valve head whose stem or spindle abuts aresilient diaphragm clamped at its edge in the casing and hav ing itsopposite sides responsive respectively to the downstream or outletpressure of a fluid such as steam, and to regulating pressure such as aspring or air.

2. Description of the Prior Art Prior art regulators having largecapacity or flow volume are large, cumbersome and costly. Also suchvalves operate with a large pressure drop between the outlet ordownstream pressure and the inlet or upstream pressure.

SUMMARY A primary object of the present invention is to provide aregulator which is small and has greater capacity or flow and lesspressure drop in relation to its size than prior regulators.

The invention especially contemplates in a regulator of the general typedescribed with a piston valve, the provision of a double venturi tubeextending across the outlet port of. the regulator and having its endscommunicating, respectively,

with a chamber beneath the diaphragm and a chamber beneath'the pistonvalve, and also having an orifice in its wall facing in the direction ofthe fluid flow through the outlet whereby during operation of theregulator the pressure is lowered under the diaphragm and under thepiston valve and the pressure is increased at the valve. The greater thedifferential between these pressures may be, the greater will be theopening of the valve so that the volume of outlet flow will be increasedand the pressure drop will be decreased.

Another object of the invention is to provide novel and improved meansfor releasably locking or clamping the adjusting knob for the diaphragmspring with a minimum of possibility of unintentionally altering theposition of the knob after the desired adjustment has been made.

The invention also contemplates a novel and improved piston valve of thesame diameter as the valve seat to provide space in the casing for astrainer to filter the fluid before it reaches the valve.

BRIEF DESCRIPTIONS OF THE DRAWING DESCRIPTION OF THE PREFERREDEMBODIMENTS Specifically describing the invention, the valve casing isshown as comprising a body A and a cover B secured on the body by screwthreads 1 and having clamped between them a diaphragm C. The valve bodyhas an inlet passage 2 and an outlet passage 3 separated by a partition4 in which is a valve port 5. Between the diaphragm C and the top wallor partition 6 of the body is a closed space or chamber 7. v

The valve port has a seat 8 disposed at one end of an outlet chamber 9which is coaxial with the diaphragm C, and cooperative with the valveseat is a piston valve 10, slidably mounted in a valve cylinder 11 inthe wall of which a packing ring 12 to prevent leakage between the valveand the cylinder wall. The valve is of smaller diameter than the outletchamber 9 and has an O-ring 13 secured exteriorly thereon at one end toengage the valve seat 8 for closing the valve port. A spring 13anormally biases the valve into closed position, and a thrust pin 14 isabuttingly interposed between the valve and the diaphragm.

An outlet duct 15 extends from the outlet chamber to the outlet passage3 with its axis approximately parallel to the axis of the passage; andpreferably the diameter of the outlet duct is less than that of theoutlet chamber, so that the velocity of flow of the fluid from theoutlet chamber is increased. Extending across the outlet duct with itsaxis perpendicular to the axis of the duct and approximately in adiametral plane of the duct, is a venturi tube 16 whose ends communicatewith the closed space 7 beneath the diaphragm and with the valvecylinder 11 beneath the valve, respectively. The tube has an orifice 17in its side wall facing in the direction of the flow of the fluidthrough the outlet duct. To establish communication between the tube andthe valve cylinder, the valve body has a passage 18 extending from oneend of the tube to an annular space 19 which is formed at the inner endof a screw plug 20 screwed into an opening 21 in the valve bodycoaxially with the valve port and having a frustoconical surface 20a atits inner end to engage the edge of an opening 22 in the valve body toprevent communication of the inlet passage 2 with the valve cylinder.The space 19 is formed between the inner end of plug 20 and the wall ofthe opening 21, and a passage 23 is formed in the plug to establishcommunication between the space 19 and the end of the valve cylinder 11.

During the operation of the regulator the diaphragm is subject to aregulating pressure by a compression spring 24 and when the piston valve10 is open, the fluid in the inlet passage tube will flow past the endof the valve into the outlet chamber and through the outlet duct aroundthe venturi tube into the outlet passage; and, therefore, the diaphragmC and the valve 10 will be subject to the fluid pressure produced by thefluid flow through the outlet duct past the venturi tube to the outletpassage. This pressure is lowered under the diaphragm and under thepiston valve, and the pressure is increased in the outlet chamber. Thegreater the differential between these pressures may be, the greaterwill be the opening of the valve so that the volume of outlet flow willbe increased and the pressure drop will be decreased. It will beunderstood by those skilled that by varying the pressure of spring 24 onthe diaphragm the outlet pressure and pressure differential may bevaried as desired.

The spring 24 is shown as mounted in a chamber 25 in the cover B, withone end abutting the diaphragm and the other end abutting a nut 26 whichhas a screw threaded connection with a regulator screw 27 but isnonrotatable in the cover so that by the rotation of the screw the nutwill move longitudinally of the screw. The screw has a flange 28abutting the end of the casing wall and the screw projects outwardlythroughan opening 29 in the end wall of the casing. Connected to theprojecting end of the screw is an inverted cupshaped knob 30 fitted overthe end of the casing cover B with its side wall 31 extending into anannular recess 32 formed between the wall of the casing and a coaxialexterior flange 33 on the casing. The flange 33 is longitudinallyslotted at 34 so that the portions between the slots are resilient, andthe edge of the flange has a frustoconical surface 33a which coacts witha frustoconical surface 35 on the inner side of a clamping or lockingring 36 which is screwed on the exterior of the flange so that when thering is rotated in one direction the casing flange is compressed to gripor clamp the sidewall of the knob between the casing flange and thecasing wall, thereby to hold the knob in its adjusted position.

It is desirable in such regulators to provide a screen to filter solidparticles from the inflowing fluid before they reach the valve wall, andas indicated herein before, the piston valve 11 is smaller in diameterthan the valve .seat 8 and provides adequate space in the body A for acylindrical screen 37 which has one end abutting the plug 20 and itsother end abuttinga shoulder 38 on the partition 4.

It will thus be seen that the invention provides a small regulator thathas a greater capacity or volume of outflow and a smaller pressure dropin relation to its size than prior regulators.

lclaim:

l. A fluid pressure regulator comprising a casing having inlet andoutlet passages and a partition between said passages provided with avalve port to afford communication between said inlet passage and anoutlet chamber which has an outlet duct which leads to said outletpassage and is smaller in cross section than said outlet chamber, saidcasing having a valve cylinder in which is a piston valve forcontrolling flow of fluid through said valve port and normally springbiased to cause one end thereof to close said port, a diaphragm securedin said casing and forming a closed space between itself and the side ofthe partition opposite said valve, a thrust pin slidably mounted in saidpartition and abuttingly interposed between said piston valve and saiddiaphragm, a venturi tube extending across said outlet duct and havingan orifice in its wall facing in the direction of fluid flow throughsaid outlet duct, the ends of said tube communicating with said closedspace and with said valve cylinder beneath the other end of said pistonvalve, respectively, whereby said piston valve and the side of saiddiaphragm in said closed space are subject to fluid pressure produced bythe fluid flow through said outlet duct past said venturi tube to saidoutlet passage, and means for applying regulating pressure to theopposite side of said diaphragm.

2. A fluid pressure regulator as defined in claim 1 wherein said valveport is at one end of said outlet chamber and has a valve seat for saidend of said valve, said casing has an opening coaxial with said valveseat, there is a screw plug separably fitted in said opening and havingtherein said valve cylinder in which said valve is mounted, and saidscrew plug has a passage communicating at one end with said venturi tubeand at its other end with said valve cylinder.

3. A fluid pressure regulator as defined in claim 1 wherein said casinghas a chamber at the second-mentioned side of said diaphragm, thelast-named means comprises an adjusting screw rotatably mounted in saidcasing and having a nut mounted relatively nonrotatably thereon andmovable longitudinally thereof, a compression spring interposed betweensaid nut and said diaphragm, and an inverted cup-shaped knob fixed onsaid screw and having a coaxial side wall fitted over said casing whichhas a coaxial exterior flange providing between itself and the wall ofthe casing an annular recess into which extends the side wall of saidknob, said flange on the casing being slotted and resilient and having afrustoconical surface at its edge, and a clamping ring screw threaded onsaid casing flange and having a frustoconical surface to coact with saidfrustoconical surface on said casing flange for compressing said flangeto clamp said side wall of the knob between said casing flange and thecasing wall and thereby hold the knob in adjusted position. 1

4. A fluid pressure regulator as defined in claim 1 wherein said valveport is at one end of said outlet chamber and has a valve seat for saidend of the valve, said outlet duct has its axis perpendicularto the axisof said outlet chamber and parallel to the axis of said outlet passage,and said venturi tube has its axis perpendicular to the axis of saidoutlet duct and lying in a diametral plane of said duct.

5. A fluid pressure regulator as defined in claim 4 wherein said pistonvalve is smaller in diameter than said valve seat and has an O-ringpacking secured exteriorly thereto to engage said valve seat for closingsaid port.

1. A fluid pressure regulator comprising a casing having inlet andoutlet passages and a partition between said passages provided with avalve port to afford communication between said inlet passage and anoutlet chamber which has an outlet duct which leads to said outletpassage and is smaller in cross section than said outlet chamber, saidcasing having a valve cylinder in which is a piston valve forcontrolling flow of fluid through said valve port and normally springbiased to cause one end thereof to close said port, a diaphragm securedin said casing and forming a closed space between itself and the side ofthe partition opposite said valve, a thrust pin slidably mounted in saidpartition and abuttingly interposed between said piston valve and saiddiaphragm, a venturi tube extending across said outlet duct and havingan orifice in its wall facing in the direction of fluid flow throughsaid outlet duct, the ends of said tube communicating with said closedspace and with said valve cylinder beneath the other end of said pistonvalve, respectively, whereby said piston valve and the side of saiddiaphragm in said closed space are subject to fluid pressure produced bythe fluid flow through said outlet duct past said venturi tube to saidoutlet passage, and means for applying regulating pressure to theopposite side of said diaphragm.
 2. A fluid pressure regulator asdefined in claim 1 wherein said valve port is at one end of said outletchamber and has a valve seat for said end of said valve, said casing hasan opening coaxial with said valve seat, there is a screw plug separablyfitted in said opening and having therein said valve cylinder in whichsaid valve is mounted, and said screw plug has a passage communicatingat one end with said venturi tube and at its other end with said valvecylinder.
 3. A fluid pressure regulator as defined in claim 1 whereinsaid casing has a chamber at the second-mentioned side of saiddiaphragm, the last-named means comprises an adjusting screw rotatablymounted in said casing and having a nut mounted relatively nonrotatablythereon and movable longitudinally thereof, a compression springinterposed between said nut and said diaphragm, and an invertedcup-shaped knob fixed on said screw and having a coaxial side wallfitted over said casing which has a coaxial exterior flange providingbetween itself and the wall of the casing an annular recess into whichextends the side wall of saiD knob, said flange on the casing beingslotted and resilient and having a frustoconical surface at its edge,and a clamping ring screw threaded on said casing flange and having afrustoconical surface to coact with said frustoconical surface on saidcasing flange for compressing said flange to clamp said side wall of theknob between said casing flange and the casing wall and thereby hold theknob in adjusted position.
 4. A fluid pressure regulator as defined inclaim 1 wherein said valve port is at one end of said outlet chamber andhas a valve seat for said end of the valve, said outlet duct has itsaxis perpendicular to the axis of said outlet chamber and parallel tothe axis of said outlet passage, and said venturi tube has its axisperpendicular to the axis of said outlet duct and lying in a diametralplane of said duct.
 5. A fluid pressure regulator as defined in claim 4wherein said piston valve is smaller in diameter than said valve seatand has an O-ring packing secured exteriorly thereto to engage saidvalve seat for closing said port.